Fix media bytes ukm

This CL changes media bytes to be recorded on every delta update,
instead of at response completion (which may miss some responses that
have not completed by pageload end). Also changes logic to treat all
video/*, audio/* mimetypes as video responses.

Change-Id: Ib78861227147978c34ed1d28dd7b24fc63600253
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2079513Reviewed-by: Ryan Sturm <ryansturm@chromium.org>
Reviewed-by: Michael Crouse <mcrouse@chromium.org>
Commit-Queue: rajendrant <rajendrant@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745537}

chrome/browser/page_load_metrics/observers/ukm_page_load_metrics_observer.cc

@@ -258,6 +258,18 @@ void UkmPageLoadMetricsObserver::OnResourceDataUseObserved(
   for (auto const& resource : resources) {
     network_bytes_ += resource->delta_bytes;
 
+    if (blink::IsSupportedImageMimeType(resource->mime_type)) {
+      image_total_bytes_ += resource->delta_bytes;
+      if (!resource->is_main_frame_resource)
+        image_subframe_bytes_ += resource->delta_bytes;
+    } else if (media::IsSupportedMediaMimeType(resource->mime_type) ||
+               base::StartsWith(resource->mime_type, "audio/",
+                                base::CompareCase::SENSITIVE) ||
+               base::StartsWith(resource->mime_type, "video/",
+                                base::CompareCase::SENSITIVE)) {
+      media_bytes_ += resource->delta_bytes;
+    }
+
     // Only sum body lengths for completed resources.
     if (!resource->is_complete)
       continue;
@@ -265,12 +277,6 @@ void UkmPageLoadMetricsObserver::OnResourceDataUseObserved(
       js_decoded_bytes_ += resource->decoded_body_length;
       if (resource->decoded_body_length > js_max_decoded_bytes_)
         js_max_decoded_bytes_ = resource->decoded_body_length;
-    } else if (blink::IsSupportedImageMimeType(resource->mime_type)) {
-      image_total_bytes_ += resource->received_data_length;
-      if (!resource->is_main_frame_resource)
-        image_subframe_bytes_ += resource->received_data_length;
-    } else if (media::IsSupportedMediaMimeType(resource->mime_type)) {
-      media_bytes_ += resource->received_data_length;
     }
     if (resource->cache_type !=
         page_load_metrics::mojom::CacheType::kNotCached) {